Buggy code:
public class Utils { public static TraversalDescription td_RESULT = Traversal . description ( ) . breadthFirst ( ) . relationships ( RESULT , OUTGOING ) ; public static TraversalDescription td_eval_IS = Traversal . description ( ) . breadthFirst ( ) . relationships ( _ , OUTGOING ) ; public static TraversalDescription upIS = Traversal . description ( ) . breadthFirst ( ) . relationships ( _ , INCOMING ) ; @ Deprecated public static List < Relationship > getSuffixes ( final Node node ) { } public static PipedInput < QCAVector > getByREF ( PFlow pf ) { } public static PipedInput < QCAVector > getByREF ( PFlow pf , final Relationship op ) { } private static PipedOutput < QCAVector > evaluable ( final PFlow pf , final Relationship r , final PipedOutput < QCAVector > out , final Relationship op ) throws IOException , InterruptedException { Statement s = Statements . relationshipType ( r ) ; if ( ( s instanceof Query ) || ( s instanceof Evaluable ) ) { PipedInput < QCAVector > in = Evaluator . _ . execute ( new PFlow ( pf ) , r ) ; for ( QCAVector e : in ) { PFlow _pf_ = new PFlow ( pf ) ; _pf_ . addContextPoint ( e ) ; Relationship result = e . getAnswer ( ) ; if ( ( ( result . isType ( REF ) ) || ( result . isType ( org . animotron . statement . operator . REF . _ ) ) ) || ( result . isType ( THE . _ ) ) ) { out . write ( e ) ; } else { for ( QCAVector rr : Utils . eval ( _pf_ , e ) ) { out . write ( rr ) ; } } } } else { <START_BUG> out . write ( new QCAVector ( null , r ) ) ; <END_BUG> } return out ; } public static PipedInput < QCAVector > getTheRelationships ( PFlow pf , Relationship r ) throws IOException { } public static void getTheRelationships ( PFlow pf , Relationship r , PipedOutput < QCAVector > out ) { } public static PipedInput < QCAVector > eval ( PFlow pf , QCAVector vector ) throws IOException { } public static Node getSingleREF ( final Node node ) { } @ Deprecated public static Relationship getByREF ( final Relationship r ) { } public static boolean results ( PFlow pf ) { } public static boolean results ( PFlow pf , byte [ ] hash ) { } public static boolean results ( Relationship op , PFlow pf ) { } public static boolean results ( Relationship op , PFlow pf , byte [ ] hash ) { } public static boolean haveContext ( Node node ) { } public static boolean haveContext ( PFlow pf ) { } public static Relationship relax ( Relationship relation ) { } public static long relaxedId ( Relationship relation ) { } public static Relationship createResult ( final PFlow pf , final Node node , final Relationship r , final RelationshipType rType ) { } public static Relationship createResult ( final PFlow pf , final QCAVector [ ] context , final Node node , final Relationship r , final RelationshipType rType ) { } public static Relationship createResult ( final PFlow pf , final Node node , final Relationship r , final RelationshipType rType , final byte [ ] hash ) { } public static Relationship createResult ( final PFlow pf , final QCAVector [ ] context , final Node node , final Relationship r , final RelationshipType rType , final byte [ ] hash ) { } public static void debug ( Statement st , Relationship op , Set < Node > thes ) { } public static String name ( Node theNode ) { } No newline ; at end ; of file ; }

Fix:
out . write ( new QCAVector ( op , r ) ) ;